% of the city's economy is tied to defense spending. and in response to sea level rise,thenavyhasbeen replacing 14 piers at a cost of $35 million to $40 million apiece. >> sea level here is coming up for lots of reasons. there is no reason for it to go down. it just keeps coming up. >> reporter: larry atkinson heads the climate change and sea level rise institute at old dominion university. >> there is anecdotal evidence and there is real evidence that we have from the tide gauges we have. we can measure this. the science is simple. >> reporter: atkinson is part of a team of scientists the state of virginia has hired to study flooding. an early draft of the bill in the state assembly that funded the study drew criticism from some conservatives. the virginia tea party described the study on its website as: "more wasted tax dollars for more ridiculous studies designed to separate us from our money and control all land and water use." the final bill avoided the phrases sea level rise and climate change and won overwhelming bipartisan support this year. >> some people have tried to spin i